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Chronically Implanted Intracranial Electrodes: Tissue Reaction And Electrical Changes., Andrew Campbell, Chengyuan Wu Aug 2018

Chronically Implanted Intracranial Electrodes: Tissue Reaction And Electrical Changes., Andrew Campbell, Chengyuan Wu

Department of Neurosurgery Faculty Papers

The brain-electrode interface is arguably one of the most important areas of study in neuroscience today. A stronger foundation in this topic will allow us to probe the architecture of the brain in unprecedented functional detail and augment our ability to intervene in disease states. Over many years, significant progress has been made in this field, but some obstacles have remained elusive-notably preventing glial encapsulation and electrode degradation. In this review, we discuss the tissue response to electrode implantation on acute and chronic timescales, the electrical changes that occur in electrode systems over time, and strategies that are being investigated …


Sex Differential In 15-Hydroxyprostaglandin Dehydrogenase Levels In The Lumen Of Human Intracranial Aneurysms., Nohra Chalouhi, Pascal Jabbour, Mario Zanaty, Robert M. Starke, James Torner, Daichi Nakagawa, David M. Hasan Oct 2017

Sex Differential In 15-Hydroxyprostaglandin Dehydrogenase Levels In The Lumen Of Human Intracranial Aneurysms., Nohra Chalouhi, Pascal Jabbour, Mario Zanaty, Robert M. Starke, James Torner, Daichi Nakagawa, David M. Hasan

Department of Neurosurgery Faculty Papers

BACKGROUND: Aspirin is a promising medical therapy for the prevention of intracranial aneurysm (IA) rupture. Recently, we found that men have a better response to aspirin than women. The purpose of this study was to determine whether a sex differential exists in the level of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in the lumen of human IAs.

METHODS AND RESULTS: Consecutive patients undergoing coiling or stent-assisted coiling for a saccular IA at our institution were enrolled. Two samples (A and B) were collected from IA lumens, and the plasma level of 15-PGDH was measured using an ELISA-based method. The study included 38 patients, …


Management Of Cerebral Cavernous Malformations: From Diagnosis To Treatment, Nikolaos Mouchtouris, Nohra Chalouhi, Md, Ameet Chitale, Robert Starke, Stavropoula Tjoumakaris, Robert H. Rosenwasswer Md, P. M. Jabbour Jan 2015

Management Of Cerebral Cavernous Malformations: From Diagnosis To Treatment, Nikolaos Mouchtouris, Nohra Chalouhi, Md, Ameet Chitale, Robert Starke, Stavropoula Tjoumakaris, Robert H. Rosenwasswer Md, P. M. Jabbour

Department of Neurosurgery Faculty Papers

No abstract provided.


Critical Role Of Tnf-Α In Cerebral Aneurysm Formation And Progression To Rupture., Robert M Starke, Nohra Chalouhi, Md, Pascal Jabbour Md, Stavropoula Tjoumakaris, L. Fernando Gonzalez, Robert H. Rosenwasswer Md, Kosuke Wada, Kenji Shimada, David M Hasan, Nigel H Greig, Gary K Owens, Aaron Dumont Apr 2014

Critical Role Of Tnf-Α In Cerebral Aneurysm Formation And Progression To Rupture., Robert M Starke, Nohra Chalouhi, Md, Pascal Jabbour Md, Stavropoula Tjoumakaris, L. Fernando Gonzalez, Robert H. Rosenwasswer Md, Kosuke Wada, Kenji Shimada, David M Hasan, Nigel H Greig, Gary K Owens, Aaron Dumont

Department of Neurosurgery Faculty Papers

BACKGROUND: Alterations in TNF-α expression have been associated with cerebral aneurysms, but a direct role in formation, progression, and rupture has not been established.

METHODS: Cerebral aneurysms were induced through hypertension and a single stereotactic injection of elastase into the basal cistern in mice. To test the role of TNF-α in aneurysm formation, aneurysms were induced in TNF-α knockout mice and mice pretreated with the synthesized TNF-α inhibitor 3,6'dithiothalidomide (DTH). To assess the role of TNF-α in aneurysm progression and rupture, DTH was started 6 days after aneurysm induction. TNF-α expression was assessed through real-time PCR and immunofluorescence staining.

RESULTS: …


Therapeutic Implications Of Estrogen For Cerebral Vasospasm And Delayed Cerebral Ischemia Induced By Aneurysmal Subarachnoid Hemorrhage., Dale Ding, Robert M Starke, Aaron S Dumont, Gary K Owens, David M Hasan, Nohra Chalouhi, Md, Ricky Medel, Chih-Lung Lin Mar 2014

Therapeutic Implications Of Estrogen For Cerebral Vasospasm And Delayed Cerebral Ischemia Induced By Aneurysmal Subarachnoid Hemorrhage., Dale Ding, Robert M Starke, Aaron S Dumont, Gary K Owens, David M Hasan, Nohra Chalouhi, Md, Ricky Medel, Chih-Lung Lin

Department of Neurosurgery Faculty Papers

Cerebral vasospasm (CV) remains the leading cause of delayed morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). However, increasing evidence supports etiologies of delayed cerebral ischemia (DCI) other than CV. Estrogen, specifically 17 β -estradiol (E2), has potential therapeutic implications for ameliorating the delayed neurological deterioration which follows aneurysmal SAH. We review the causes of CV and DCI and examine the evidence for E2-mediated vasodilation and neuroprotection. E2 potentiates vasodilation by activating endothelial nitric oxide synthase (eNOS), preventing increased inducible NOS (iNOS) activity caused by SAH, and decreasing endothelin-1 production. E2 provides neuroprotection by increasing thioredoxin expression, decreasing c-Jun N-terminal …


Flow-Diversion Panacea Or Poison?, Mario Zanaty, Nohra Chalouhi, Md, Stavropoula I. Tjoumakaris, Robert H. Rosenwasswer Md, L. Fernando Gonzalez, Pascal Jabbour Md Feb 2014

Flow-Diversion Panacea Or Poison?, Mario Zanaty, Nohra Chalouhi, Md, Stavropoula I. Tjoumakaris, Robert H. Rosenwasswer Md, L. Fernando Gonzalez, Pascal Jabbour Md

Department of Neurosurgery Faculty Papers

Endovascular therapy is now the treatment of choice for intracranial aneurysms (IAs) for its efficacy and safety profile. The use of flow diversion (FD) has recently expanded to cover many types of IAs in various locations. Some institutions even attempt FD as first line treatment for unruptured IAs. The most widely used devices are the pipeline embolization device (PED), the SILK flow diverter (SFD), the flow redirection endoluminal device (FRED), and Surpass. Many questions were raised regarding the long-term complications, the optimal regimen of dual antiplatelet therapy, and the durability of treatment effect. We reviewed the literature to address these …


Stereotactic Radiosurgery With Neoadjuvant Embolization Of Larger Arteriovenous Malformations: An Institutional Experience, Richard Dalyai, Thana Theofanis, Robert Starke, Nohra El-Chalouhi, Md, George M. Ghobrial Md, Pascal Jabbour, Md, Aaron Dumont, L. Fernando Gonzalez, David Gordon, Robert Rosenwasser, Stavropoula Tjoumakaris Jan 2014

Stereotactic Radiosurgery With Neoadjuvant Embolization Of Larger Arteriovenous Malformations: An Institutional Experience, Richard Dalyai, Thana Theofanis, Robert Starke, Nohra El-Chalouhi, Md, George M. Ghobrial Md, Pascal Jabbour, Md, Aaron Dumont, L. Fernando Gonzalez, David Gordon, Robert Rosenwasser, Stavropoula Tjoumakaris

Department of Neurosurgery Faculty Papers

Objective. This study investigates the safety and efficacy of a multimodality approach combining staged endovascular embolizations with subsequent SRS for the management of larger AVMs. Methods. Ninety-five patients with larger AVMs were treated with staged endovascular embolization followed by SRS between 1996 and 2011. Results. The median volume of AVM in this series was 28 cm3 and 47 patients (48%) were Spetzler-Martin grade IV or V. Twenty-seven patients initially presented with hemorrhage. Sixty-one patients underwent multiple embolizations while a single SRS session was performed in 64 patients. The median follow-up after SRS session was 32 months (range 9-136 months). …


Extending The Indications Of Flow Diversion To Small, Unruptured, Saccular Aneurysms Of The Anterior Circulation., Nohra Chalouhi, Md, Robert M Starke, Steven Yang, Cory D Bovenzi, Stavropoula Tjoumakaris, David Hasan, L. Fernando Gonzalez, Robert H. Rosenwasswer Md, Pascal Jabbour Md Jan 2014

Extending The Indications Of Flow Diversion To Small, Unruptured, Saccular Aneurysms Of The Anterior Circulation., Nohra Chalouhi, Md, Robert M Starke, Steven Yang, Cory D Bovenzi, Stavropoula Tjoumakaris, David Hasan, L. Fernando Gonzalez, Robert H. Rosenwasswer Md, Pascal Jabbour Md

Department of Neurosurgery Faculty Papers

BACKGROUND AND PURPOSE: Flow diverters are currently indicated for treatment of large and complex intracranial aneurysms. The purpose of this study was to determine whether the indications of flow diversion can be safely extended to unruptured, small, saccular aneurysms (<10 >mm) of the anterior circulation.

METHODS: Forty patients treated with the pipeline embolization device (PED) were matched in a 1:4 fashion with 160 patients treated with stent-assisted coiling based on patient age, sex, aneurysm location, and aneurysm size. Procedural complications, angiographic results, and clinical outcomes were analyzed and compared.

RESULTS: The rate of periprocedural complications was 5% in the PED …


Review Of Cerebral Aneurysm Formation, Growth, And Rupture., Nohra Chalouhi, Md, Brian L Hoh, David Hasan Dec 2013

Review Of Cerebral Aneurysm Formation, Growth, And Rupture., Nohra Chalouhi, Md, Brian L Hoh, David Hasan

Department of Neurosurgery Faculty Papers

No abstract provided.


Malignant Peripheral Nerve Sheath Tumor (Mpnst): An Overview With Emphasis On Pathology, Imaging And Management Strategies, Timothy C. Beer Jun 2012

Malignant Peripheral Nerve Sheath Tumor (Mpnst): An Overview With Emphasis On Pathology, Imaging And Management Strategies, Timothy C. Beer

Department of Neurosurgery Faculty Papers

Presentation: 20 slides

MPNSTs are rare malignancies that are classically associated with pre-existing plexiform neurofibromas in neurofibromatosis type 1 (NF-1) patients, but also occur in association with radiation as well as sporadically in patients with no known risk factors. The typical presentation of sporadic MPNST is a new painless enlarging mass. The typical presentation of MPNST in an NF-1 patient is rapid enlargement or new onset of pain associated with a pre-existing plexiform neurofibroma. Although both MPNST and benign neurofibromas share in common the absence of neurofibromin function due to loss of both NF-1 alleles, malignant transformation to MPNST requires …


Nociceptive Neuropeptide Increases And Periorbital Allodynia In A Model Of Traumatic Brain Injury., Melanie B. Elliott, Michael L. Oshinsky, Peter S. Amenta, Olatilewa Awe, Jack I. Jallo Jun 2012

Nociceptive Neuropeptide Increases And Periorbital Allodynia In A Model Of Traumatic Brain Injury., Melanie B. Elliott, Michael L. Oshinsky, Peter S. Amenta, Olatilewa Awe, Jack I. Jallo

Department of Neurosurgery Faculty Papers

OBJECTIVE: This study tests the hypothesis that injury to the somatosensory cortex is associated with periorbital allodynia and increases in nociceptive neuropeptides in the brainstem in a mouse model of controlled cortical impact (CCI) injury.

METHODS: Male C57BL/6 mice received either CCI or craniotomy-only followed by weekly periorbital von Frey (mechanical) sensory testing for up to 28 days post-injury. Mice receiving an incision only and naïve mice were included as control groups. Changes in calcitonin gene-related peptide (CGRP) and substance P (SP) within the brainstem were determined using enzyme-linked immunosorbent assay and immunohistochemistry, respectively. Activation of ionized calcium-binding adaptor molecule-1-labeled …


Management Of Sexual Disorders In Spinal Cord Injured Patients., Vafa Rahimi-Movaghar, Alexander R Vaccaro May 2012

Management Of Sexual Disorders In Spinal Cord Injured Patients., Vafa Rahimi-Movaghar, Alexander R Vaccaro

Department of Neurosurgery Faculty Papers

Spinal cord injured (SCI) patients have sexual disorders including erectile dysfunction (ED), impotence, priapism, ejaculatory dysfunction and infertility. Treatments for erectile dysfunction include four steps. Step 1 involves smoking cessation, weight loss, and increasing physical activity. Step 2 is phosphodiesterase type 5 inhibitors (PDE5I) such as Sildenafil (Viagra), intracavernous injections of Papaverine or prostaglandins, and vacuum constriction devices. Step 3 is a penile prosthesis, and Step 4 is sacral neuromodulation (SNM). Priapism can be resolved spontaneously if there is no ischemia found on blood gas measurement or by Phenylephrine. For anejaculatory dysfunction, massage, vibrator, electrical stimulation and direct surgical biopsy …


Early Versus Delayed Decompression For Traumatic Cervical Spinal Cord Injury: Results Of The Surgical Timing In Acute Spinal Cord Injury Study (Stascis), Michael G. Fehlings, Alexander Vaccaro, Jefferson R. Wilson, Anoushka Singh, David W. Cadotte, James S. Harrop, Bizhan Aarabi, Christopher Shaffrey, Marcel Dvorak, Charles Fisher, Paul Arnold, Eric M. Massicotte, Stephen Lewis, Raja Rampersaud Feb 2012

Early Versus Delayed Decompression For Traumatic Cervical Spinal Cord Injury: Results Of The Surgical Timing In Acute Spinal Cord Injury Study (Stascis), Michael G. Fehlings, Alexander Vaccaro, Jefferson R. Wilson, Anoushka Singh, David W. Cadotte, James S. Harrop, Bizhan Aarabi, Christopher Shaffrey, Marcel Dvorak, Charles Fisher, Paul Arnold, Eric M. Massicotte, Stephen Lewis, Raja Rampersaud

Department of Neurosurgery Faculty Papers

Background: There is convincing preclinical evidence that early decompression in the setting of spinal cord injury (SCI) improves neurologic outcomes. However, the effect of early surgical decompression in patients with acute SCI remains uncertain. Our objective was to evaluate the relative effectiveness of early (,24 hours after injury) versus late ($24 hours after injury) decompressive surgery after traumatic cervical SCI.

Methods: We performed a multicenter, international, prospective cohort study (Surgical Timing in Acute Spinal Cord Injury Study: STASCIS) in adults aged 16–80 with cervical SCI. Enrolment occurred between 2002 and 2009 at 6 North American centers. The primary outcome was …


Redefining Onyx Hd 500 In The Flow Diversion Era., Richard Tyler Dalyai, Ciro Randazzo, George Ghobrial, L Fernando Gonzalez, Stavropoula I Tjoumakaris, Aaron S Dumont, Robert H Rosenwasser, Pascal Jabbour Jan 2012

Redefining Onyx Hd 500 In The Flow Diversion Era., Richard Tyler Dalyai, Ciro Randazzo, George Ghobrial, L Fernando Gonzalez, Stavropoula I Tjoumakaris, Aaron S Dumont, Robert H Rosenwasser, Pascal Jabbour

Department of Neurosurgery Faculty Papers

We report the largest US case series results using Onyx HD-500 (EV3), a new liquid embolic agent, in the successful treatment of 21 patients with wide-neck intracranial aneurysms (mean size 4.5 mm), which are at increased risk of incomplete occlusion or recanalization with standard endovascular intervention utilizing detachable platinum coils. All aneurysms were located in the anterior circulation, and three aneurysms presented as acute subarachnoid hemorrhages. Complete aneurysm occlusion was present in 19 of 21 patients (90%). On six-month followup, one patient with an initially small residual neck progressed to total occlusion. Aneurysm recanalization was not detected in any patients …


An Evaluation Of Neuroplasticity And Behavior After Deep Brain Stimulation Of The Nucleus Accumbens In An Animal Model Of Depression., Steven M Falowski, Ashwini Sharan, Beverly A S Reyes, Carl Sikkema, Patricia Szot, Elisabeth J Van Bockstaele Dec 2011

An Evaluation Of Neuroplasticity And Behavior After Deep Brain Stimulation Of The Nucleus Accumbens In An Animal Model Of Depression., Steven M Falowski, Ashwini Sharan, Beverly A S Reyes, Carl Sikkema, Patricia Szot, Elisabeth J Van Bockstaele

Department of Neurosurgery Faculty Papers

BACKGROUND: Recent interest has demonstrated the nucleus accumbens (NAcc) as a potential target for the treatment of depression with deep brain stimulation (DBS).

OBJECTIVE: To demonstrate that DBS of the NAcc is an effective treatment modality for depression and that chemical and structural changes associated with these behavioral changes are markers of neuroplasticity.

METHODS: A deep brain stimulator was placed in the NAcc of male Wistar-Kyoto rats. Groups were divided into sham (no stimulation), intermittent (3 h/d for 2 weeks), or continuous (constant stimulation for 2 weeks). Exploratory and anxietylike behaviors were evaluated with the open-field test before and after …


Acute Effects Of A Selective Cannabinoid-2 Receptor Agonist On Neuroinflammation In A Model Of Traumatic Brain Injury., Melanie B Elliott, Ronald F Tuma, Peter S Amenta, Mary F Barbe, Jack I Jallo Jun 2011

Acute Effects Of A Selective Cannabinoid-2 Receptor Agonist On Neuroinflammation In A Model Of Traumatic Brain Injury., Melanie B Elliott, Ronald F Tuma, Peter S Amenta, Mary F Barbe, Jack I Jallo

Department of Neurosurgery Faculty Papers

Proposed therapeutic strategies for attenuating secondary traumatic brain injury (TBI) include modulation of acute neuroimmune responses. The goal of this study was to examine the acute effects of cannabinoid-2 receptor (CB(2)R) modulation on behavioral deficits, cerebral edema, perivascular substance P, and macrophage/microglial activation in a murine model of TBI. Thirty male C57BL/6 mice underwent sham surgery, or cortical contusion impact injury (CCI). CCI mice received vehicle or the CB(2)R agonist 0-1966 at 1 and 24 h after injury. Performance on the rotarod, forelimb cylinder, and open-field tests were evaluated before and at 48 h after sham or CCI surgery. Cerebral …


A Phase I/Iia Clinical Trial Of A Recombinant Rho Protein Antagonist In Acute Spinal Cord Injury., Michael G Fehlings, Nicholas Theodore, James Harrop, Gilles Maurais, Charles Kuntz, Chris I Shaffrey, Brian K Kwon, Jens Chapman, Albert Yee, Allyson Tighe, Lisa Mckerracher May 2011

A Phase I/Iia Clinical Trial Of A Recombinant Rho Protein Antagonist In Acute Spinal Cord Injury., Michael G Fehlings, Nicholas Theodore, James Harrop, Gilles Maurais, Charles Kuntz, Chris I Shaffrey, Brian K Kwon, Jens Chapman, Albert Yee, Allyson Tighe, Lisa Mckerracher

Department of Neurosurgery Faculty Papers

Multiple lines of evidence have validated the Rho pathway as important in controlling the neuronal response to growth inhibitory proteins after central nervous system (CNS) injury. A drug called BA-210 (trademarked as Cethrin(®)) blocks activation of Rho and has shown promise in pre-clinical animal studies in being used to treat spinal cord injury (SCI). This is a report of a Phase I/IIa clinical study designed to test the safety and tolerability of the drug, and the neurological status of patients following the administration of a single dose of BA-210 applied during surgery following acute SCI. Patients with thoracic (T2-T12) or …


Awake Vs. Asleep Placement Of Spinal Cord Stimulators: A Cohort Analysis Of Complications Associated With Placement, Steven M. Falowski, Md, Amanda Celii Md, Anthony K. Sestokas Phd, Daniel M. Schwartz Phd, Craig Matsumoto Mpas, Ashwini Sharan Md Dec 2010

Awake Vs. Asleep Placement Of Spinal Cord Stimulators: A Cohort Analysis Of Complications Associated With Placement, Steven M. Falowski, Md, Amanda Celii Md, Anthony K. Sestokas Phd, Daniel M. Schwartz Phd, Craig Matsumoto Mpas, Ashwini Sharan Md

Department of Neurosurgery Faculty Papers

Introduction: Patients will typically undergo awake surgery for permanent implantation of SCS in an attempt to optimize electrode placement using patient feedback about the distribution of stimulation-induced paresthesia. The present study compared efficacy of first-time electrode placement under awake conditions with that of neurophysiologically-guided placement under general anesthesia.

Methods: A retrospective review was performed of 387 SCS surgeries among 259 patients which included 167 new stimulator implantation to determine whether first time awake surgery for placement of spinal cord stimulators is preferable to non-awake placement.

Results: The incidence of device failure for patients implanted using neurophysiologically-guided placement under general anesthesia …


Emergency Reversal Of Antiplatelet Agents In Patients Presenting With An Intracranial Hemorrhage: A Clinical Review, Peter G. Campbell, Md, Anish Sen, Bs, Sanjay Yadla, Md, Pascal Jabbour, Md, Jack Jallo, Md, Phd Aug 2010

Emergency Reversal Of Antiplatelet Agents In Patients Presenting With An Intracranial Hemorrhage: A Clinical Review, Peter G. Campbell, Md, Anish Sen, Bs, Sanjay Yadla, Md, Pascal Jabbour, Md, Jack Jallo, Md, Phd

Department of Neurosurgery Faculty Papers

Abstract

Objective: Prehospital use of antiplatelet agents has been associated with an increased risk for ICH as well as a secondary increase in ICH volume after the initial hemorrhage. Strategies to reestablish platelet aggregation are used in clinical practice, but without any established guidelines or recommendations. This article serves to evaluate the literature regarding “reversal” of antiplatelet agents in neurosurgical populations.

Methods: PUBMED and MEDLINE databases were searched for publications from 1966 to 2009 relating to intracranial hemorrhage and antiplatelet agents. The reference sections of recent articles, guidelines and reviews were reviewed and pertinent articles identified. Studies were classified by …


Multiport Minimally Invasive Skull Base Surgery: How Many Ports Are Too Many?, Yaron A. Moshel, Theodore H. Schwartz Jun 2010

Multiport Minimally Invasive Skull Base Surgery: How Many Ports Are Too Many?, Yaron A. Moshel, Theodore H. Schwartz

Department of Neurosurgery Faculty Papers

Surgical access to the ventral skull base has evolved considerably over the past several years with the introduction of minimally invasive endoscopic and endoscope-assisted approaches. The accompanying manuscript by Ciporen et al. demonstrates an addition to this growing body of literature in their description of the feasibility of multiportal endoscopic approaches to the skull base, particularly the precaruncular transorbital approach, in a series of cadaver dissections. Similar to laparoscopic abdominal surgery, which utilizes multiple small ports to improve visualization and manipulation, they envision a modular combination of approaches that allows an endoscope to be placed in one port and surgery …


Occipital Nerve Stimulator Systems: Review Of Complications And Surgical Techniques, Steven Falowski, Dajie Wang, Arvind Sabesan, Ashwini Sharan Apr 2010

Occipital Nerve Stimulator Systems: Review Of Complications And Surgical Techniques, Steven Falowski, Dajie Wang, Arvind Sabesan, Ashwini Sharan

Department of Neurosurgery Faculty Papers

Introduction: Stimulation of the occipital nerves is becoming more widely accepted in the treatment of occipital neuritis and migraine disorders.

Objective: Presently, equipment available for spinal cord stimulation is adapted for insertion into the subcutaneous space over the occipital nerves. Many technical factors need to be reassessed to optimize the therapy.

Methods: We performed a retrospective review of patients implanted from 2003 to 2007 at a single center. We aimed to analyze the rate of surgical complications related to implantation technique. A total of 28 patients were present for analysis. Patients were followed up to 60 months with a mean …


Interaction Of The Mu-Opioid Receptor With Gpr177 (Wntless) Inhibits Wnt Secretion: Potential Implications For Opioid Dependence., Jay Jin, Saranya Kittanakom, Victoria Wong, Beverly A S Reyes, Elisabeth J Van Bockstaele, Igor Stagljar, Wade Berrettini, Robert Levenson Jan 2010

Interaction Of The Mu-Opioid Receptor With Gpr177 (Wntless) Inhibits Wnt Secretion: Potential Implications For Opioid Dependence., Jay Jin, Saranya Kittanakom, Victoria Wong, Beverly A S Reyes, Elisabeth J Van Bockstaele, Igor Stagljar, Wade Berrettini, Robert Levenson

Department of Neurosurgery Faculty Papers

BACKGROUND: Opioid agonist drugs produce analgesia. However, long-term exposure to opioid agonists may lead to opioid dependence. The analgesic and addictive properties of opioid agonist drugs are mediated primarily via the mu-opioid receptor (MOR). Opioid agonists appear to alter neuronal morphology in key brain regions implicated in the development of opioid dependence. However, the precise role of the MOR in the development of these neuronal alterations remains elusive. We hypothesize that identifying and characterizing novel MOR interacting proteins (MORIPs) may help to elucidate the underlying mechanisms involved in the development of opioid dependence. RESULTS: GPR177, the mammalian ortholog of Drosophila …


Traumatic Thoracic Asia A Examinations And Potential For Clinical Trials, James S. Harrop, Md, Mitchell G. Maltenfort, Phd, Fred H. Geisler, Md, Phd, William Coleman, Phd, Linda A.T. Jones, Pt, Ms, Edward Wirth, Md, Alexander Vaccaro, Md, Phd Nov 2009

Traumatic Thoracic Asia A Examinations And Potential For Clinical Trials, James S. Harrop, Md, Mitchell G. Maltenfort, Phd, Fred H. Geisler, Md, Phd, William Coleman, Phd, Linda A.T. Jones, Pt, Ms, Edward Wirth, Md, Alexander Vaccaro, Md, Phd

Department of Neurosurgery Faculty Papers

Study Design: Retrospective review of prospective database

Objectives: To define the variability of neurologic examination and recovery after non-penetrating complete thoracic spinal cord injuries (ASIA A).

Background Data: Neurologic examinations after SCI can be difficult and inconsistent. Unlike cervical SCI patients, alterations in thoracic (below T1) complete SCI (ASIA A – based on the ASIA Impairment Scale [AIS]) patients’ exams are based only on sensory testing, thus changes in the neurological level (NL) are determined only by sensory changes.

Methods: A retrospective review of the placebo control patients in a multicenter prospective database utilized for the pharmacologic trial of Sygen. …


The Efficacy Of Surgical Decompression Before 24 Hours Versus 24 To 72 Hours In Patients With Spinal Cord Injury From T1 To L1--With Specific Consideration On Ethics: A Randomized Controlled Trial., Vafa Rahimi-Movaghar, Soheil Saadat, Alexander R Vaccaro, Seyed Mohammad Ghodsi, Mohammad Samadian, Arya Sheykhmozaffari, Seyed Mohammad Safdari, Bahram Keshmirian Jan 2009

The Efficacy Of Surgical Decompression Before 24 Hours Versus 24 To 72 Hours In Patients With Spinal Cord Injury From T1 To L1--With Specific Consideration On Ethics: A Randomized Controlled Trial., Vafa Rahimi-Movaghar, Soheil Saadat, Alexander R Vaccaro, Seyed Mohammad Ghodsi, Mohammad Samadian, Arya Sheykhmozaffari, Seyed Mohammad Safdari, Bahram Keshmirian

Department of Neurosurgery Faculty Papers

BACKGROUND: There is no clear evidence that early decompression following spinal cord injury (SCI) improves neurologic outcome. Such information must be obtained from randomized controlled trials (RCTs). To date no large scale RCT has been performed evaluating the timing of surgical decompression in the setting of thoracolumbar spinal cord injury. A concern for many is the ethical dilemma that a delay in surgery may adversely effect neurologic recovery although this has never been conclusively proven. The purpose of this study is to compare the efficacy of early (before 24 hours) verse late (24-72 hours) surgical decompression in terms of neurological …


In Vivo Trafficking Of Endogenous Opioid Receptors, Yulin Wang, Elisabeth J. Van Bockstaele, Lee-Yuan Liu-Chen Nov 2008

In Vivo Trafficking Of Endogenous Opioid Receptors, Yulin Wang, Elisabeth J. Van Bockstaele, Lee-Yuan Liu-Chen

Department of Neurosurgery Faculty Papers

Studies on trafficking of endogenous opioid receptors in vivo are subject of the present review. In many of the in vivo studies, the use of semi-quantitative immuno-electron microscopy is the approach of choice. Endogenous opioid receptors display differential subcellular distributions with μ opioid receptor (MOPR) being mostly present on the plasma membrane and δ- and κ-opioid receptors (DOPR and KOPR, respectively) having a significant intracellular pool. Etorphine and DAMGO cause endocytosis of the MOPR, but morphine does not, except in some dendrites. Interestingly, chronic inflammatory pain and morphine treatment promote trafficking of intracellular DOPR to the cell surface which may …


Spinal Cord Stimulation: An Update., Steven Falowski, Amanda Celii, Ashwini Sharan Jan 2008

Spinal Cord Stimulation: An Update., Steven Falowski, Amanda Celii, Ashwini Sharan

Department of Neurosurgery Faculty Papers

Spinal cord stimulation has been used in the treatment of many chronic pain disorders since 1967. In this update, the indications for spinal cord stimulation are reviewed with attention to recent publications. A focused review of the literature on abdominal and visceral pain syndromes is also provided. Furthermore, the technology has evolved from the use of monopolar electrodes to complex electrode arrays. Similarly, the power source has changed from a radio frequency-driven system to a rechargeable impulse generator. These topics are covered, along with a short discussion of implant technique. Finally, we include a review of complications of such therapy. …


Locus Ceruleus Regulates Sensory Encoding By Neurons And Networks In Waking Animals, David M. Devilbiss, Michelle E. Page, Barry D. Waterhouse Sep 2006

Locus Ceruleus Regulates Sensory Encoding By Neurons And Networks In Waking Animals, David M. Devilbiss, Michelle E. Page, Barry D. Waterhouse

Department of Neurosurgery Faculty Papers

Substantial evidence indicates that the locus ceruleus (LC)–norepinephrine (NE) projection system regulates behavioral state and state-dependent processing of sensory information. Tonic LC discharge (0.1–5.0 Hz) is correlated with levels of arousal and demonstrates an optimal firing rate during good performance in a sustained attention task. In addition, studies have shown that locally applied NE or LC stimulation can modulate the responsiveness of neurons, including those in the thalamus, to nonmonoaminergic synaptic inputs. Many recent investigations further indicate that within sensory relay circuits of the thalamus both general and specific features of sensory information are represented within the collective firing patterns …


Pro-Opiomelanocortin Co-Localizes With Corticotropin-Releasing Factor In Axon Terminals Of The Noradrenergic Nucleus Locus Coeruleus, Beverly A.S. Reyes, Julia D. Glaser, Ronaldo Magtoto, Elisabeth K. Van Bockstaele Apr 2006

Pro-Opiomelanocortin Co-Localizes With Corticotropin-Releasing Factor In Axon Terminals Of The Noradrenergic Nucleus Locus Coeruleus, Beverly A.S. Reyes, Julia D. Glaser, Ronaldo Magtoto, Elisabeth K. Van Bockstaele

Department of Neurosurgery Faculty Papers

We previously demonstrated that the opioid peptide, enkephalin, and corticotropin-releasing factor (CRF) are occasionally co-localized in individual axon terminals but more frequently converge on common dendrites in the locus coeruleus (LC). To further examine potential opioid co-transmitters in CRF afferents, we investigated the distribution of proopiomelanocortin (POMC), the precursor that yields the potent bioactive peptide, ß-endorphin, with respect to CRF immunoreactivity using immunofluorescence and immunoelectron microscopic analyses of the LC. Coronal sections were collected through the dorsal pontine tegmentum of rat brain and processed for immunocytochemical detection of POMC and CRF or tyrosine hydroxylase (TH). POMC-immunoreactive processes exhibited a distinct …


Dopamine-D1 And Δ-Opioid Receptors Co-Exist In Rat Striatal Neurons, L. M. Ambrose-Lanci, S. M. Gallagher, E. M. Unterwald, E. J. Van Bockstaele Feb 2006

Dopamine-D1 And Δ-Opioid Receptors Co-Exist In Rat Striatal Neurons, L. M. Ambrose-Lanci, S. M. Gallagher, E. M. Unterwald, E. J. Van Bockstaele

Department of Neurosurgery Faculty Papers

Cocaine’s enhancement of dopaminergic neurotransmission in the mesolimbic pathway plays a critical role in the initial reinforcing properties of this drug. However, other neurotransmitter systems are also integral to the addiction process. A large body of data indicates that opioids and dopamine together mediate emotional and reinforced behaviors. In support of this, cocaine-mediated increases in activation of dopamine D1 receptors (D1R) results in a desensitization of δ-opioid receptor (DOR) signaling through adenylyl cyclase (AC) in striatal neurons. To further define cellular mechanisms underlying this effect, the subcellular distribution of DOR and D1R was examined in the rat dorsolateral striatum. Dual …


Global Cns Gene Transfer For A Childhood Neurogenetic Enzyme Deficiency: Canavan Disease., Paola Leone, Christopher G Janson, Scott J Mcphee, Matthew J During Aug 1999

Global Cns Gene Transfer For A Childhood Neurogenetic Enzyme Deficiency: Canavan Disease., Paola Leone, Christopher G Janson, Scott J Mcphee, Matthew J During

Department of Neurosurgery Faculty Papers

The neurogenetic prototypic disease on which we chose to test our gene therapy strategy is Canavan disease (CD). CD is an autosomal recessive leukodystrophy associated with spongiform degeneration of the brain. At present the disease is uniformly fatal in affected probands. CD is characterized by mutations in the aspartoacylase (ASPA) gene, resulting in loss of enzyme activity. In this review, recent evidence is summarized on the etiology and possible treatments for CD. In particular, we discuss two gene delivery systems representing recent advances in both viral and liposome technology: a novel cationic liposome-polymer-DNA (LPD) complex, DCChol/DOPE-protamine, as well as recombinant …